Excavators, and similar earth-moving equipment typically utilize hydraulic actuators, which may include cylinders and hydraulic motors, to operate functions of the machine, such as movement of an implement. In some control systems, electronic controls send current to a solenoid to activate a valve spool. Typically, if there are no commands from the operator, the solenoids are not activated and the valve spools are in a neutral position. In such neutral position the valve spools block flow to the hydraulic actuators. In the event of a malfunction in the system, it is possible that one or more valve spools may be shifted when there is no active command from the operator. This may result in unintended operation of the function of the machine controlled by the valve spool, for example unintended movement of an implement.
U.S. Pat. No. 6,176,126 (“Tsuruga et al.”) issued Jan. 23, 2001 describes an engine speed control system for a construction machine arranged in association with a hydraulic circuit. The engine speed control system is provided with pilot valves arranged in a pilot line to control traveling, booms and the like. Automatic idling control or its cancellation is provided in accordance with signals from pressure sensors. While beneficial, a system may be needed for detecting uncommanded positioning of a valve spool that controls a function of the machine and subsequently taking action to stop the flow of fluid to the hydraulic actuators upon such detection.